HELMHOLTZ IN BERLIN 



usually in the morning, after the wearied brain had 

 been refreshed by sleep, or while walking up a hill- 

 side, with pure air and bright sunny weather, that the 

 truth flashed before his mental vision. Even the 

 smallest amount of alcohol he found interfered with 

 his mental work. He then reduced his views to writ- 

 ing, and took great pains in giving correct expression 

 to what he wished to communicate. In literary com- 

 position he was extremely fastidious, often writing the 

 manuscript six times over, and next day, even after 

 this severe ordeal, he was never satisfied with what he 

 had written. 



It is not necessary to define the position of Helm- 

 holtz amongst scientific thinkers. His works bear 

 their own evidence. There is a general consensus of 

 opinion that he is one of the greatest men of the 

 present century. To find one like him in mental 

 power and width of range, we must go back to such 

 intellectual giants as Descartes and Leibnitz, and 

 even when he is compared with them, it must not be 

 forgotten how enormously broader was the field of 

 science in the time of Helmholtz than in the seven- 

 teenth century. The only English philosopher with 

 whom he may be compared is Thomas Young. 

 Both were remarkable for versatility and originality ; 

 both had the same wide range of knowledge ; both 

 were manifold men of science ; both were physio- 

 logists and physicists ; the researches of both were 

 fundamental. But Helmholtz was, as a mathema- 

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